1. Field of the Invention
The present invention relates to a timepiece with a calendar mechanism having plural date indicators for indicating a date. More specifically, the invention relates to an analog timepiece with a calendar mechanism including a first date indicator and a second indicator for indicating a units numeral of a date, and a third date indicator for indicating a tens numeral of a date.
2. Description of the Prior Art
(1) Description of Terms:
Generally, a machine body including a drive portion of a timepiece is referred to as “movement”. A state of constituting a finished product by attaching a dial, a hand to a movement and putting the movement in a timepiece case is referred to as “complete” of a timepiece. In both sides of a main plate constituting a base plate of a timepiece, a side of providing glass of a timepiece case, that is, a side of providing a dial is referred to as “back side” of a movement or “glass side” or “dial side”. In both sides of a main plate, a side of providing a case back of a timepiece case, that is, a side opposed to a dial is referred to as “top side” or “case back side” of movement. A train wheel integrated to “top side” of a movement is referred to as “top train wheel”. A train wheel integrated to “bottom side” of movement is referred to as “bottom train wheel”. Generally, “12 o'clock side” indicates a side of arranging a graduation in correspondence with 12 o'clock of a dial in an analog type timepiece. “12 o'clock direction” indicates a direction directed to “12 o'clock side” from a rotational center of an indicator in an analog type timepiece. Further, “3 o'clock side” indicates a side of arranging a graduation in correspondence with 3 o'clock of a dial in an analog type timepiece. “3 o'clock direction” indicates a direction directed to “3 o'clock side” from a rotational center of an indicator. Further, “6 o'clock side” indicates a side of arranging a graduation in correspondence with 6 o'clock of a dial in an analog type timepiece. “6 o'clock direction” indicates a direction directed to “6 o'clock side” from a rotational center of an indicator in an analog type timepiece. Further, “9 o'clock side” indicates a side of arranging a graduation in correspondence with 9 o'clock of a dial. “9 o'clock direction” indicates a direction directed to “9 o'clock side” from a rotational center of an indicator in an analog type timepiece. Further, there is a case of indicating a side of arranging other graduation of a dial as in “2 o'clock direction”, “2 o'clock side”.
(2) Timepiece with Calendar Mechanism of Background Art:
An explanation will be given of a timepiece with a calendar mechanism of a background art including a first date indicator indicating a position of 1 of a date, and a second date indicator indicating a position of 10 of a date as follows.
(2.1) Timepiece with Calendar Mechanism of First Type of Background Art:
In reference to FIG. 26, a timepiece with a calendar mechanism of a first type of a background art includes two date indicators 822, 824 overlapped each other at least partially. The first date indicator 822 provides date indication of a position of 1, and the second indicator 824 provides date indication of a position of 10. The first date indicator 822 is provided with numerals of “0”, “1” through “9”, that is, 10 pieces of numerals in a circumferential direction. The second date indicator 824 is provided with two sets of numerals from “0” through “3”, that is, 8 pieces of numerals in a circumferential direction. A drive mechanism includes a 24 hour indicator 820 rotating by one rotation per 24 hours by rotation of an hour wheel 816, an operating lever 844 operated by rotating the 24 hour indicator 820, and other wheel or the like for control. By operating the operating lever 844, a program wheel 850 is rotated, the first date indicator 822 is rotated by a first date indicator drive wheel 852, and the second date indicator 824 is rotated by a second date indicator drive wheel 854. Rotation of the first date indicator 822 is rectified by a first date indicator jumper 862. Rotation of the second date indicator 824 is rectified by a second date indicator jumper 864 (refer to, for example, Patent Reference 1).
(2.2) Timepiece with Calendar Mechanism of Second Type of Background Art:
In reference to FIG. 27, a timepiece with a calendar mechanism of a second type of a background art includes a 1 position circular disk 932 indicating a position of 1 of a date, and a 10 position circular disk 931 indicating a position of 10 of a date. A 1 pinion 933 is fixed to the 1 position circular disk 932. A 1 position jumper 936 maintains an angular position of a 1 position pinion 933. A 10 position pinion 934 is fixed to the 10 position circular disk 931. A 10 position jumper 940 maintains an angular position of the 10 position pinion 934. The 1 position pinion 933 is brought in mesh with an upper half of a teeth row of a date gear 908. The 1 position circular disk 932 is provided with numerals of “0”, “1” through “9”, that is, 10 pieces of numerals in a circumferential direction. The 10 position circular disk 931 is provided with two sets of numerals from “0” through “3” and two of “0”, that is, 10 pieces of numerals in a circumferential direction. Respective hooks of a drive apparatus 906 are brought in mesh with a teeth row of the date gear 908, thereby, teeth of the date gear 908 are made to advance 1 pitch per 1 day. The 10 position pinion 934 is driven by 1 pitch by an intermediate movable part 937. The intermediate movable part 937 is driven by 1 pitch by the date gear 908 by way of an idle gear 938 (refer to, for example, Patent Reference 2).
(3) Lists of Patent References
[Patent Reference 1] European Patent Application Publication No. 1070996 A1
[Patent Reference 2] JP-A-2000-147148
According to a timepiece with a calendar mechanism of a first type of the background art, a drive mechanism for driving the first date indicator 822 and the second date indicator 824 includes the 24 hour indicator 820, the operating lever 844 and other wheel for control and therefore, there poses a problem that a structure of the drive mechanism is complicated and an area occupied by the drive mechanism is large. Further, according to the timepiece with the calendar mechanism of the second type of the background art, the 10 position pinion 934 is driven by the date gear 908 by way of the intermediate movable part 937 and the idle gear 938 and therefore, there poses a problem that a drive mechanism for driving the 10 position circular disk 931 is complicated and an area occupied by the drive mechanism is large. Further, a timepiece with a calendar mechanism of a background art poses a problem that a drive mechanism is complicated, and a rotational load of the drive mechanism is large. According to a timepiece with a calendar mechanism of a background art, 10 pieces of numerals indicating dates are provided in a circumferential direction of a date indicator and therefore, it is difficult to enlarge a size of numerals indicating the dates.
It is an object of the invention to provide a timepiece with a calendar mechanism that includes three date indicators comprising two date indicators for indicating a position of 1 of a date (i.e., a units numeral of the date) and one date indicator for indicating a position of 10 of a date (i.e., a tens numeral of the date), and a drive mechanism for driving the three date indicators by a compact mechanism having a simple structure. Further, it is another object of the invention to provide a timepiece with a calendar mechanism including a date indicator having a date character which is large and easy to see. Further, it is another object of the invention to provide a timepiece with a calendar mechanism in which a rotational load of a drive mechanism is small.